Here’s a serious question: Why the sudden fad for SBRs, SBSs, and suppressed weapons? As I see it, an NFA weapon has no real advantage over a non-NFA weapon, and some disadvantages (how do you AIWB a suppressed M&P?), plus it’s a Fed magnet. If you ever use one in self-defense, you can bet on the weapon’s NFA status being used against you.
(Yes, I know they’re fun. I’ve shot them. I’ve shot a suppressed full-auto MP5, and I still smile every time I think about it. But I don’t see the point in going through all the hassle just to have something that practically guarantees you more hassles.)